JP2629545B2 - Method and apparatus for measuring slag surface and electrode position in incineration ash melting furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring a slag surface and an electrode position of an incineration ash melting furnace for measuring a slag surface and an electrode position in a melting furnace for melting waste such as incineration ash and sewage sludge. Things.

[0002]

2. Description of the Related Art Waste such as incinerated ash of urban garbage and sewage sludge contains various inorganic and organic substances, and if these are buried as they are, serious secondary pollution is caused. Therefore, in recent years, incineration ash melting furnaces have been used to detoxify such wastes. In this melting furnace, electric current is passed between the electrodes loaded inside, resistance heating, most of the waste is turned into molten slag, which is a vitreous melt, and the remainder is turned into molten metal of metal. To discharge. In order to operate the melting furnace efficiently, it is desirable that a predetermined amount of waste is sequentially charged into the melting furnace, a large amount of molten slag is continuously taken out, and a small amount of molten metal is taken out intermittently. The condition in this case is that the slag surface in the furnace is always kept at a predetermined position so that the height difference between the slag surface of the molten slag and the slag port is always constant, and furthermore, the waste is efficiently melted. It is necessary that the tip of the electrode is located at a certain depth from the slag surface of the molten slag.

[0003] By the way, since the upper part of this melting furnace is sealed, the position of the slag surface in the furnace cannot be known. And since the ratio of organic matter and inorganic matter contained in the waste is not known, even if a predetermined amount of waste is put into the melting furnace, the position of the slag surface fluctuates. There is a risk that molten slag may overflow from the furnace when the position of the slag surface is too high because the slag cannot be reused because the slag is clogged or the metal is mixed with the molten slag to be taken out. Further, since the position of the metal surface also fluctuated, it was not possible to judge when to remove the metal. Furthermore, it is impossible to know whether the tip of the electrode is located at a certain depth from the slag surface of the molten slag, and discard when the tip of the electrode is not located at a certain depth from the slag surface of the molten slag. The material could not be melted efficiently. Therefore, in order to avoid such a situation, know the position of the slag surface in the furnace and the position of the electrode in the molten slag, adjust the removal of slag and metal accordingly to make the slag surface constant, It is required to adjust the position of the electrode.

[0004]

Conventionally, there has been no method or apparatus for knowing the position of the slag surface and the position of the electrode in the incinerator ash melting furnace having a closed upper part. The present invention has been made in order to solve such problems, and in a melting furnace in which an upper part is sealed, incineration ash melting in which the position of a slag surface in the furnace and the position of an electrode can be known. An object of the present invention is to obtain a method and an apparatus for measuring a slag surface and an electrode position of a furnace.

[0005]

The slag surface and electrode position measuring device of the incineration ash melting furnace according to the present invention has a closed upper part, and a plurality of electrodes filled in the furnace are heated by electric resistance heating. A wire feeder that feeds a metal wire at a predetermined feed rate from the furnace top of the incineration ash melting furnace that melts the incineration ash charged to the terminal plate provided at the furnace bottom, and a wire feeder. An encoder for measuring a feed amount of the sent wire, a voltmeter for measuring a voltage between the wire and the terminal plate, and a furnace based on the wire feed amount measured by the encoder and a voltage change measured by the voltmeter. And a calculating means for calculating the position of the slag surface and the electrode position therefrom.

[0006]

In the present invention, first, the voltage between each electrode and the terminal plate provided on the furnace bottom is measured, and then a plurality of electrodes are respectively moved so that these measured voltages coincide with each other. After adjusting, and afterwards or without adjusting the movable operation of the electrodes, the metal wire is fed by a wire feeder from the furnace top to the terminal plate provided on the furnace bottom at a predetermined feed amount, and the encoder is Measure the feed amount of the wire sent out by the wire feeding device, and measure the voltage change between the wire and the terminal plate caused by the current flowing between the electrodes in the molten slag during the wire feeding with a voltmeter, The position of the slag surface in the furnace and the electrode position therefrom are calculated based on the wire feed amount measured by the encoder by the calculation means and the voltage change measured by the voltmeter. Position and tip position of the electrode from its lug surfaces can be known.

[0007]

FIG. 1 is a configuration diagram showing a slag surface and an electrode position measuring device of an incineration ash melting furnace according to an embodiment of the present invention. FIG. 2 is a plan view showing an arrangement of electrodes and wires of the incineration ash melting furnace. FIG.
Is a waveform diagram of the voltmeter of the measuring device when the molten slag is 1400 ° C., and FIG. 4 is a graph showing a relationship between a voltage change of the voltmeter of the measuring device and a wire feeding time. In the figure, 1 is an incineration ash melting furnace, 2 is a furnace main body of the incineration ash melting furnace 1, 3 is a lid placed on the upper part of the furnace main body 2, 4 is a vertically movable through the lid 3, and a lower end. Are two electrodes reaching the vicinity of the furnace bottom, 5 is two incineration ash inlets provided on the lid 2, and 6 is the furnace body 2.
, A metal tap hole provided at the bottom of the furnace wall of the furnace body 2, a terminal plate 8 provided at the bottom of the furnace body 2, and an electrode 4 at the bottom of the furnace body 2. , 4 for applying an AC voltage.

Reference numeral 10 denotes a metal wire having a diameter of 4.8 mm;
Penetrates the lid 2 from the furnace top of the melting furnace 1 to the terminal plate 6 at the furnace bottom.
This is a wire feeder for feeding the wire 10 at a predetermined feed amount toward the vehicle, and includes a pair of rollers 12 and a motor 13 for driving the rollers 12. 14 is a wire feeding device 1
An encoder for measuring the feed amount of the wire 10 sent out by 1; 15, an AC voltmeter for measuring the voltage between the wire 10 and the terminal plate 8; 16, a wire feed amount of the encoder 14 and the voltage of the AC voltmeter 15 Calculation means 17 for calculating the slag surface from the furnace top and the electrode position therefrom based on the change, and 17 is a level indicator for displaying the slag surface and the electrode position therefrom based on the calculation value of the calculation means 16.

Next, the case where the method of the present invention is carried out using the slag surface and electrode position measuring device of the incineration ash melting furnace of the above embodiment will be described with reference to FIGS. First,
The incineration ash introduced from the incineration ash inlet 5 into the furnace body 2 is melted by resistance heating generated by the application of an AC voltage of the power supply 9 between the electrodes 4 and 4 to become molten slag and molten metal, and the molten slag layer is formed. S and molten metal layer M are formed.
At this time, the electrodes 4, 4 are held such that their tips keep a certain distance from the slag surface of the molten slag layer S. When the molten slag layer and the molten metal layer are formed in the furnace main body 2 in this manner, the wire 10 is fed by the wire feeder 11 from the furnace top of the furnace main body 2 toward the terminal plate 8 on the furnace bottom in a predetermined manner. We send by quantity. At this time, the encoder 14 determines the number of rotations of the motor 13 from the wire feeding device 11.
The feed amount of the wire 10 sent out is measured.
At the same time as the wire 10 is fed, the wire 10 generated by the current flowing between the electrodes 4 and 4 in the molten slag layer S
The AC voltmeter 15 measures the voltage change between the terminal voltmeter 8 and the terminal plate 8, and the measured value of the AC voltmeter 15 is sent to the calculating means 16. Further, the wire feed amount measured by the encoder 14 is also sent to the calculating means 17. The calculating means 16 calculates the slag surface from the furnace top and the electrode position therefrom based on the voltage change of the AC voltmeter 15 and the wire feed amount of the encoder 14. The level indicator 17 displays the slag surface of the molten slag layer S from the furnace top of the furnace main body 2 and the position of the electrodes from the calculated value of the calculating means 17.

As described above, the calculating means 16 uses the AC voltmeter 1
The slug surface and the electrode position therefrom can be obtained by calculation from the voltage change of No. 5 and the wire feed amount of the encoder 14 for the following reason. FIG. 3 shows a voltage change of the AC voltmeter 15 accompanying the feeding of the wire 10 when the temperature of the molten slag in the furnace main body 2 is 1400 ° C. As shown in FIG. 3, when the wire 10 is in the furnace space, the AC voltmeter 15 indicates 0 V, and when the wire 10 reaches the slag surface of the molten slag layer S, the AC voltmeter 15 indicates 1.7 V. When the voltage rises and reaches the substantially central position of the molten slag layer S, the voltage reaches a maximum of 4 V, and then the voltage gradually decreases to 0.7 V immediately before reaching the metal surface of the molten metal layer M.
It shows 0V when it reaches the metal surface. As described above, the voltage changes in a mountain-like manner between the time when the wire 10 reaches the slag surface of the molten slag layer S and the time when the wire 10 reaches the metal surface of the molten metal layer M is substantially the same as that in the thickness direction of the molten slag layer S. The tip of the electrodes 4 and 4 is located at the center position, and the current generated in the shunt circuit between the wire 10 and the terminal plate 8 formed around the current path between the electrodes 4 and 4 is the current between the electrodes 4 and 4. This is because when the wire 10 is close to the road, that is, when the tip of the wire 10 is close to the electrode 4, the voltage increases as the distance increases, and the voltage also changes accordingly. Therefore, the time when the voltage indicated by the AC voltmeter 15 is the maximum is when the tip of the wire 10 is closest to the electrode 4, which means that the tip position of the wire 10 indicates the tip position of the electrode 4. Therefore, the tip position of the electrode 4 can be found by finding the tip position of the wire 10 when the voltage indicated by the AC voltmeter 15 is the maximum. The reason why the AC voltmeter 15 indicates 0 V when the wire 10 is in the furnace space is that an electric current does not flow between the wire 10 and the terminal plate 8 because the wire 10 is in an insulated state. When it reaches 0 V, it shows 0 V because the wire 10 and the terminal plate 8 are short-circuited and have the same potential.

FIG. 3 shows a voltage change of the AC voltmeter 15 accompanying the feeding of the wire 10 when the temperature of the molten slag in the furnace body 2 is 1400 ° C. FIG.
The relationship between the lapse of the feeding time of the wire 10 and the voltage change of the voltmeter 16 at 1400 ° C. is shown. In these figures, t0 to t1 indicate the time required for the wire tip to reach the slag surface from the furnace top, and t1 to t2 indicate the time required for the wire tip to reach the metal surface from the slag surface.
t3 indicates the time required for the tip of the wire to reach the tip of the electrode from the slag surface. Therefore, when the time of the voltage change of the AC voltmeter 15 is converted from the feed amount of the wire 10, the position of the slag surface of the molten slag layer S in the furnace main body 2 (distance from the furnace top) and the melting from the slag surface The position of the metal surface of the metal layer M and the position of the tip of the electrode 4 from the slag surface are known. For example, as shown in FIG.
If t0 to t1 is 8 seconds, the distance from the furnace top to the slag surface is 348 mm, and t1 to t2 is 11 seconds. Therefore, the distance from the slag surface to the metal surface, that is, the depth of the slag hot water is 4 mm / s.
Since 78.5 mm and t1 to t3 are 5 seconds, it can be seen that the distance from the slag surface to the tip of the electrode is 267.5 mm.
In this example, it is assumed that the slag surface and the position of the electrode from the slag surface are measured shortly before and it is confirmed that the tips of the two electrodes are at the same position.

FIG. 5 is a block diagram of an apparatus for performing a method for measuring a slag surface and an electrode position in an incineration ash melting furnace according to another embodiment of the present invention. The same components as those of the embodiment shown in FIG. 1 are denoted by the same reference numerals, and description of the components is omitted. 18 is a first voltmeter for measuring the voltage between one electrode 4 and the terminal plate 8,
Reference numeral 19 denotes a second voltmeter for measuring a voltage between the other electrode 4 and the terminal plate 8. This embodiment is based on the premise that the tips of the two electrodes are not at the same position, and is performed when the slag surface and the electrode position therefrom have not been measured before. The first voltmeter 18 and the second voltmeter 19 measure the voltage between the terminal and the terminal plate 8 respectively. Next, looking at the voltage values indicated by the first voltmeter 18 and the second voltmeter 19, if these voltage values do not match,
The two electrodes 4 and 4 are movably adjusted so as to coincide with each other. The reason why the electrodes 4 and 4 are movably adjusted is that the voltage V0 between the electrodes 4 and 4 is the voltage V1 between one electrode 4 and the terminal plate 8 and the voltage V1 between the other electrode 4 and the terminal plate 8. Voltage V
V1 = V2 when the tips of the two electrodes are at the same position, and V1> V2 or V1 <when the tips of the two electrodes are not at the same position.
V2.

Thereafter, the metal wire 10 is directed toward the terminal plate 8 by the wire feeder 11.
From the furnace top of the furnace body 2 toward the terminal plate 8 on the furnace bottom at a predetermined feed amount, and the encoder 14 measures the feed amount of the wire 10. Simultaneously with the sending of the wire 10, a change in voltage between the wire 10 and the terminal plate 8 is measured by the AC voltmeter 15, and the measured value is sent to the calculating means 16. The amount of wire feed measured by the encoder 14 is also calculated by the arithmetic means 17.
Send to The calculating means 16 calculates the slag surface from the furnace top and the electrode position therefrom based on the voltage change of the AC voltmeter 15 and the wire feed amount of the encoder 14, and the level indicator 17 calculates the furnace main body from the calculated value of the calculating means 17. The slag surface of the molten slag layer S from the furnace top of No. 2 and the electrode position therefrom are displayed.

In the above embodiment, the AC voltage of the arc power supply device 9 is applied between the electrodes 4 and 4 and the AC voltage is output using the AC voltmeter 15. When a voltage is applied, the DC voltage changes in the same manner as the AC voltage from when the wire 10 reaches the slag surface of the molten slag layer S until it reaches the metal surface of the molten metal layer M. Therefore, a DC voltmeter is used. Even if you do the same effect,
Of course, it produces an effect.

[0015]

As described above, according to the present invention, if the slag surface and the position of the electrode from the slag surface have not been measured before, the voltage between each electrode and the terminal plate provided on the furnace bottom is first measured. Are measured, and then a plurality of electrodes are movably adjusted so that the voltages to be measured coincide with each other.If the slag surface and the position of the electrode from the slag surface were measured immediately before, adjust the movement of the electrodes. Instead, a metal wire is fed from the furnace top to a terminal plate provided on the furnace bottom at a predetermined feed rate, and is generated by an electric current flowing between the electrodes in the molten slag during the wire feed. Since the voltage change between the wire and the terminal plate was measured, and the position of the slag surface in the furnace and the electrode position therefrom were calculated and obtained based on the feed amount of the wire and the voltage change. Inside the incineration ash melting furnace Easily electrode position of the slag surface and from the definitive molten slag layer, yet has the effect that it is possible to know for sure.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a slag surface and an electrode position measuring device of an incineration ash melting furnace according to one embodiment of the present invention.

FIG. 2 is a plan view showing an arrangement of electrodes and wires of an incineration ash melting furnace.

FIG. 3 is a waveform diagram of a voltmeter of the measuring device when the molten slag is 1400 ° C.

FIG. 4 is a graph showing a relationship between a voltage change of a voltmeter of the measuring device and a wire feeding time.

FIG. 5 is a configuration diagram of an apparatus for performing a method for measuring a slag surface and an electrode position of an incineration ash melting furnace according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Incineration ash melting furnace 4 Electrode 8 Terminal plate 10 Wire 11 Wire feeder 14 Encoder 15 AC voltmeter 16 Calculation means

Claims (3)

(57) [Claims] 1. A method for measuring a slag surface and an electrode position of an incineration ash melting furnace for melting incineration ash charged into a furnace by electric resistance heating of a plurality of electrodes filled in the furnace with an upper portion sealed. A metal wire is fed from the furnace top to a terminal plate provided on the furnace bottom at a predetermined feed rate, and a wire generated by a current flowing between electrodes in the molten slag during the wire feed. The voltage change between the terminal plate and the terminal plate is measured, and the position of the slag surface in the furnace and the electrode position therefrom are calculated and obtained based on the feed amount of the wire and the voltage change. Slag surface and electrode position measurement method for incineration ash melting furnace. 2. A method for measuring a slag surface and an electrode position of an incineration ash melting furnace which melts incineration ash charged into the furnace by heating the plurality of electrodes filled in the furnace with the upper portion sealed. First, the voltage between each electrode and the terminal plate provided on the furnace bottom is measured, respectively, and then the plurality of electrodes are movably adjusted so that these measured voltages match each other. A metal wire is fed from the furnace top to a terminal plate provided on the furnace bottom at a predetermined feed rate, and the wire and the terminal generated by the current flowing between the electrodes in the molten slag during the wire feeding. Incineration characterized by measuring the voltage change between the plate and the electrode, and calculating the position of the slag surface in the furnace and the electrode position therefrom based on the wire feed amount and the voltage change. Slag surface and electrode position of ash melting furnace Measurement method. 3. An incineration ash melting furnace which melts incineration ash charged into the furnace by heating the plurality of electrodes filled in the furnace with the upper portion sealed and provided from the furnace top to the furnace bottom. A wire feeder that feeds a metal wire at a predetermined feed amount toward the terminal plate, and an encoder that measures the feed amount of the wire sent by the wire feeder,
A voltmeter that measures the voltage between the wire and the terminal plate,
An incineration ash melting furnace comprising: arithmetic means for calculating a position of a slag surface in the furnace and an electrode position therefrom based on a wire feed amount measured by an encoder and a voltage change measured by a voltmeter. Slag surface and electrode position measuring device.